周辺の天然記念物・トップ20

This quarry is a Site of Special Scientific Interest and well known by geologists for its phenomenal history. Packed with fossils, some of the finds here date back 100 million years. There's no public access, but you can catch glimpses of its bright high-alkaline water from the surrounding footpaths.

Chinnor, Chalk and Cement Mr. W. Benton's Cement and Lime Works opened in Chinnor in 1908, but cement making on a truly industrial scale did not begin until 1919. Output of cement from Chinnor peaked at about 5600 tonnes per week in the 1990s. Up to 120 people were employed at any one time. The cement works closed in 1999 and there are plans for the re-development of the site, using the flat areas for housing but also with opportunities for recreation and conservation in the water filled quarries The scale of chalk extraction for cement making can be seen from a short walk along the Ridgeway National Trail. The Ridgeway runs on a high causeway between the large quarries, giving views of the pits through the boundary fences. (Do not cross over or through the fences). Geology One of the chalk quarries has been protected as a geological Site of Special Scientific Interest as it has particularly good exposures of both the Lower Chalk and Middle Chalk geological layers. Both layers have given upimportant fossil ammonites.

The wetland meadows of Cock Marsh are very important for rare plant species, breeding waders and overwintering birds. Part of the site is designated as a Site of Special Scientific Interest (SSSI). The steep chalk grassland swiftly changing into marshy, acid meadows has created an ecosystem of rare and interesting species. As part of the historic channel of the Thames, the ponds here support specialist plants like water violet, marsh arrowgrass, marsh stitchwort, marsh pennywort and water hemlock. The rare sedge Cyperus fuscus (brown galingale) is found here and in only a handful of other sites in Great Britain. It relies on cattle to tread or poach the ground on the pond edges to create the perfect habitat to grow. The cattle here work hard to help to maintain a rich botanical diversity of grassland habitat. https://www.nationaltrust.org.uk/maidenhead-and-cookham-commons/trails/cookham-and-cock-marsh-walk

Archaeological Surveys undertaken in Park Wood have revealed a fascinating past for this quiet area of deciduous woodland. Lynchets and banks within the woods give evidence of ancient field systems which may date back to the late Iron Age/early Roman period (or they may be medieval). In the beech woodland opposite the pond is evidence of a late thirteenth/early fourteenth homestead in the woodlands and in Tudor times (1485 – 1603) the woodland was a deer park. Much of Park Wood was converted to beech woodland from the late 18th until the early 20th century to cater for the High Wycombe furniture industry. Associated features include sawpits, tracks and charcoal burning platforms. https://www.nationaltrust.org.uk/chilterns-countryside/trails/bradenham-beech-woods-and-bunkers-trail

Like other major valleys or gaps in the Chilterns that run approximately North-South, the Bradenham valley was predominantly formed during Pleistocene Epoch (the Ice Ages), between 2.5 million and 10,000 years ago. Like most other Chiltern valleys, it is now a dry valley because the underlying chalk is permeable to water. During the Ice Age, in permafrost conditions, water could not pass through the frozen ground. Seasonal thawing, particularly of the ice sheets to the north, would have released large amounts of water, which would have cut down into the chalk to create the present “fossil” valley. https://www.nationaltrust.org.uk/chilterns-countryside/trails/bradenham-beech-woods-and-bunkers-trail

Bluebells are well-known for forming carpets of bright blue flowers beneath our oak and beech woodlands in the late spring. At this time of year, they can also be found along hedgerows and in woodland clearings. Their spectacular floral displays are exclusive to northern Europe, with Britain containing more than half of the world’s population of bluebells. Bluebells, which are inedible members of the asparagus family of plants, are perennial bulbous herbs with flowering stems to about 50cm tall. They spend most of the year as bulbs underground and emerge to flower from mid-April onwards, although they are usually at their peak in the first two weeks of May, depending on the spring weather. Up to twenty sweetly-scented flowers are borne on a flower stalk which droops to one side. The flowers are bell-shaped and although they are usually blue, they can be white or rarely pink. https://www.nationaltrust.org.uk/chilterns-countryside/features/discover-bluebells-in-the-chiltern-countryside